From 852e49dfc375736595caec590a54e2c53843ee22 Mon Sep 17 00:00:00 2001
From: Tobias Bouschen <tobias.bouschen@googlemail.com>
Date: Wed, 20 Mar 2019 13:02:33 +0100
Subject: [PATCH] Removed unnecessary time measure vars and added error
handling
---
kernel/sched/pb.c | 64 +++++++++-----------------------------------
kernel/sched/sched.h | 26 +++++-------------
2 files changed, 19 insertions(+), 71 deletions(-)
diff --git a/kernel/sched/pb.c b/kernel/sched/pb.c
index 1edf4daa5152..d6e87803d435 100644
--- a/kernel/sched/pb.c
+++ b/kernel/sched/pb.c
@@ -1,45 +1,6 @@
-
-
-//#include "sched.h"
#include <linux/kthread.h>
#include "perf_error_detection.h"
-/*
- * Kelvin's Testcode
- */
-void set_pb_measure_on(struct pb_rq *pb)
-{
- pb->measure_k = PB_MEASURE_K_ON;
- pb->start = sched_clock();
- pb->ktime = 0;
- pb->kstart = 0;
-}
-
-EXPORT_SYMBOL(set_pb_measure_on);
-
-/*
- * Kelvin's Testcode
- */
-void set_pb_measure_off(struct pb_rq *pb_rq)
-{
- u64 runtime;
- u64 stop = sched_clock();
-
- pb_rq->measure_k = PB_MEASURE_K_OFF;
- if (stop < pb_rq->start)
- {
- printk(KERN_DEBUG "Start is greater than stop. This is a bug!\n");
- }
- runtime = stop - pb_rq->start;
- printk("Measured for %lluus detected ktime of %lluus\n", runtime, pb_rq->ktime);
-
- pb_rq->ktime = 0;
- pb_rq->kstart = 0;
- pb_rq->start = 0;
-}
-
-EXPORT_SYMBOL(set_pb_measure_off);
-
/*
* Kelvin's Testcode
*/
@@ -49,6 +10,9 @@ void set_pb_plan_size(struct pb_rq *pb_rq, unsigned int size)
}
EXPORT_SYMBOL(set_pb_plan_size);
+/*
+ * Kelvin's Testcode
+ */
//insert into pb queue (analog to enqueue)
void set_pb_plan_entry(struct pb_rq *pb_rq, unsigned int i, u64 n_instr, u64 task_id, struct task_struct *task_struct )
{
@@ -67,16 +31,16 @@ void init_pb_rq(struct pb_rq *pb_rq)
pb_rq->count_admin_cycles = 0;
pb_rq->mode = PB_DISABLED_MODE;
pb_rq->c_entry = 0;
- pb_rq->proxy_task = NULL;
pb_rq->size = 0;
pb_rq->pevent = NULL;
- pb_rq->measure_k = PB_MEASURE_K_OFF;
- pb_rq->kstart = 0;
- pb_rq->ktime = 0;
- pb_rq->start = 0;
}
EXPORT_SYMBOL(init_pb_rq);
+void finalize_pq_rq_init(struct pb_rq *pb_rq)
+{
+ pb_rq->is_initialized = 1;
+}
+
// task enters the runnable state
static void
@@ -88,12 +52,7 @@ enqueue_task_pb(struct rq *rq, struct task_struct *p, int flags)
// task exists the runnable state
static void dequeue_task_pb(struct rq *rq, struct task_struct *p, int flags)
{
- /* - check performance counter:
- * compare smaller then expected -> compute difference -> throw event
- * - unregister papi event
- * - check flags
- */
-
+ // NOP
}
static void yield_task_pb(struct rq *rq)
@@ -125,7 +84,9 @@ static struct task_struct * pick_next_task_pb(struct rq *rq,
u64 perf_counter;
u64 read_error = get_perf_counter(pb->pevent, &perf_counter);
- //TODO error handling
+ if (read_error){
+ printk(KERN_WARNING "FETCHING PERFORMACE COUNTER IN PB SCHEDULER FAILED WITH %llu\n", read_error);
+ }
terminate_perf_event(pb->pevent);
@@ -145,6 +106,7 @@ static struct task_struct * pick_next_task_pb(struct rq *rq,
if (pb->c_entry >= pb->size){
printk(KERN_DEBUG "PLAN DONE\n");
pb->mode = PB_DISABLED_MODE;
+ pb->is_initialized = 0;
}else{
int perf_init_res = init_perf_event(pb->plan[pb->c_entry], &pb->pevent);
if(perf_init_res < 0){
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index a451e57c0fab..7a7cc903f739 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -536,8 +536,6 @@ struct pb_rq {
unsigned int size;
// currently executed entry of the plan
unsigned int c_entry;
- // pointer to the dummy task
- struct task_struct *proxy_task; //TODO: We should comment this out and iterate the plan accordingly
// amount of timer consecutive timer interrupts for pb tasks
u64 n_pb_cycles;
@@ -552,17 +550,14 @@ struct pb_rq {
// one of PB_DISABLED_MODE, PB_EXEC_MODE, PB_ADMIN_MODE
int mode;
-
- //TODO: Do we still need those?
- int measure_k;
- u64 kstart;
- u64 ktime;
- u64 start;
+ // one event for each core, not for each task
+ struct perf_event *pevent;
/*
- * Per Core, nicht per Task
+ * flag determining whether the plan is completely initialized and should be run
+ * this variable must be initialized last
*/
- struct perf_event *pevent;
+ volatile int is_initialized;
};
/* Real-Time classes' related field in a runqueue: */
@@ -882,13 +877,7 @@ static inline int determine_next_mode_pb(struct rq *rq)
if (pb->c_entry < pb->size)
{
// initial switch
- if (pb->mode == PB_DISABLED_MODE &&
- //TODO:
- /*
- * We have to iterate the Plan, and think about a mechanism to signal that a plan is ready
- * to be processed - maybe set pb->size 0 when the plan is done, n when a plan with n entries is ready.
- */
- pb->proxy_task != NULL)
+ if (pb->mode == PB_DISABLED_MODE && pb->is_initialized)
{
return PB_EXEC_MODE;
}
@@ -2084,9 +2073,6 @@ extern void init_rt_rq(struct rt_rq *rt_rq);
extern void init_pb_rq(struct pb_rq *pb_rq);
extern void init_dl_rq(struct dl_rq *dl_rq);
-
-extern void set_pb_measure_off(struct pb_rq *pb_rq);
-extern void set_pb_measure_on(struct pb_rq *pb_rq);
extern void set_pb_plan_size(struct pb_rq *pb_rq, unsigned int size);
extern void set_pb_plan_entry(struct pb_rq *pb_rq, unsigned int i, u64 n_instr, u64 task_id, struct task_struct *task_struct);
--
GitLab